Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) WATANABE Zenjiro and YAMADA Etsuro,On Electro-Magnetic Measurements of Rock Drill Performances,Journal of the Mining and Metallurgical Institute of Japan,03694194,The Mining and Materials Processing Institute of Japan,1964,80,914,665-668,https://cir.nii.ac.jp/crid/1390001205982460928,https://doi.org/10.2473/shigentosozai1953.80.914_665